Pencil-holding means for pencil-sharpeners.



G. C. SPENGLER.

PENCIL HOLDING MEANS FOR PENCIL SHARPENERS.

APPLICATION FILED JAN. 24. 1912.

Patented Nov. 24, 1914.

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Al 786 C 495' 5B) [er 20 F W UNITED srrarss PATENT. oFFioE.

CHARLES C. SPENGLER, OFROCKFORD, ILLINOIS, ASSIGNOR TO AUTOMATIC PENCILSHARPENER COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF NEW YORK.

PENCIL HOLDING MEANS FOR, PENGIL-SI'IARPENERS.

To all whom it may concern:

Be it knownthat I, CHARLES C. SPENGLER,

a citizen of the United States,residing at Rockforckin the county ofWinnebago and State of Illinois, have invented certain new and usefulImprovements in Pencil-Holding Means for Pencil-Sharpeners, of which thefollowing is a specification.

This invention relates to chucks to be used on pencil sharpeners for thepurpose of holding. and rotating the pencils that are being sharpened.In some of the pencil holders or chucks heretofore produced, the jawsare pressed inwardly to grasp the pencil by means ofeither leaf orcoiled springs. I These prior chucks, however, have been foundunsatisfactoryin practice for the reason that they grip different sizesof pencilsto be sharpened with different degrees of force. To operatesatisfactorily the chuck must grip the pencil with suflicient force toinsure rotation of the latter therewith, but not tightly enough toprevent the pencil from beingdrawn or fed downwardly'to thecuttingfmeans. In previous chucks, if the relation of parts was suchthat a small-sized pencil would be gripped firmly enough to insurerotation of the pencil, then a large-sized pencil would be held sotightly that proper downward feeding movement thereof could not be had.On the other hand, if the chuck gripped a largesized pencil lightlyenough to permit free downward feeding movement thereof, a small-sizedpencil would not be engaged with suflicient force to cause rotationthereof with the chuck.

It is the object of my invention to produce a chuck which will grip allsizes of pencils with substantial uniformity. As ancillary to the mainobject of the invention it is my purpose to provide a chuck of simpleand durable construction and one which is inexpensive to manufacture. a

In the accompanying drawings, Figure 1 is a front. elevation of a pencilsharpener equipped with a pencil chuck embodying my invention. Fig. 2 isa fragmental vertical section on line 2 of Fig. 1. Fig. 3 is a verticalsection of the chuck with a large pencil Specification of LettersPatent.

Application filed January 24, 1912. Serial No. 673,094.

Patented NOV. 24, 1914.

inserted. Fig. -l is avertical section ofthe chuck with a small pencilinserted. Fig. 5 is a cross-section of the chuck and pencil on the line5 5 of Fig. 3. Fig. 6 is a fragmental plan view of the chuck with thepencil in sorted and a portion of the casing broken away to show detailsof the chuck.

The pencil sharpener to which my improvements are herein shown asapplied is of the type illustrated in the Gilfillan Patent No. 832,054,issued October 2, 1906. But it is to be understood that the chuck is notlimited in its use to any particular form of pencil sharpener.

abase l in which is slidably mounted the The sharpener comprises idrawer 2,.the upper wallofsaid base having an opening 3 therein throughwhich the shavings and dust from the pencils fall into the drawer 2.Surrounding the opening3 are guard walls at. Mounted upon the top wallof thebase 1 is a disk 5 having a plane face 5 on one side and havingaboss 6 formed upon its opposite side. Through this boss extends anopening or bore 7 adapt The opening .Textends at form, that herein showncomprising a plurality of rotating blades 8 lying against the face 5 ofthe disk 5, saidblades arranged to be rotated by means of a suitablecrank handle 9 to move successivelyover the open lower end of the bore 7so as to cut off the portion of the pencil protrudingthi'ough said lowerend. As each knife cuts off a portion of the pencil it draws the pencilbodily downward a slight distance.

"lhe'means for frictionally engaging the pencil A to rotate the latter,which I desig nate as the chuck, is rotatably,mountedupon the upper endof theboss 6, saidineans com pr1s1ng,j1n the present embodiment, asleeve 10 having an extension 1.1v at its lower end, i

whiclniin this instance,isjseatedlin a countersink in the upper end o'fthe opening or bore 7. Fixed upon the extension 11 is a toothed wheel 12adapted to be engaged by ion any suitable means for intermittentlyrotating the pencil holder or chuck. A member 13 having spring arms lilies at opposite sides of the sleeve 10 and engages the upper side ofthe toothed wheel 12 for the purpose of holding the extension 11 seatedin the countersink, and also to frictionally hold the sleeve againstrotation through momentum.

The sleeve 1.1 has a'plurality of openings 15 in its sides, above whichand suitably at tached to said sleeve, is an annular flange 16. Ahousing or cap 17 is secured to the flange 16 in any suitable way as bymeans of screws 18 threaded into said flange. housing incloses the upperportion of the sleeve 10- and the gripping means to be now described.

The gripping means comprises a plurality (in this instance four) offingers or jaws 19, which, in the exemplary embodiment herein disclosed,take substantially the. form of the letter U. The upper or free end ofone of the arms 20 of each jaw is pivotally attached to the chuck in anysuitable manner, that herein shown comprising a plurality of notches 21in the periphery of the flange 16 and above the openings 15, the freeends of the arms 20 of the jaws lying in these notches and each havinglugs 22 overlying the edges of the notches and engaging the uppersurface of the flange 16. Bosses 23 formed in the housing 17 providechambers 24% in which the upper ends of the arms 20 he, said chambersserving to hold said upper ends in proper position, but permitting thenecessary movement thereof. The other arm 25 of each of the jaws 19 isreduced at its free end,as at 26, to provide shoulders 27. Surroundingthe reduced ends 26 of the arms 25 and bearing at one end against theshoulders 27 are coiled springs 28, the other ends of which bear againstthe housing 17.

- Thefingers 1 9 and springs 28 normally ex tend diagonally with respectto the sleeve 11. By a comparison of Figs. 3 and 4, the

former figure showing a large pencil and the latter figure a smallpencil inserted into the chuck, it will be noticed that when the jaws19' are forced to their outermost position by a large pencil, thedirection of force exerted by the springs 28- is more nearly parallel tothe jaw than :when a small pencil is inserted, as shown in Fig. i. Asthe jaws are forced outwardly from their innermost position thedirection ofpressure of the springs 28 gradually shifts, from a linemore or less transverse to the extent of the jaws, toward a lineparallel to the jaws. By reason of this operation of the springs andjaws the,

eflfective gripping action of the jaws upon the pencil is maintainedsubstantially constant for all sizes of pencils. This is due to the factthat the force of the springs actu- Said.

ally transmitted to the jaws when in their outer position is less thanwhen in their innermost position, because in the former pos tion thesprings act more nearly in a line with the jaws, and thus exert part oftheir force in pulling downwardly on the pivots of the jaws, while inthe latter position the springs act in a direction at a greater anglewith respect to thejaws. And this direction of pressure of the springsgradually shifts as the jaws are moved one way or the other, with theresult that the effective gripping pressure of the jaws is maintainedconstant for all sizes of pencils.

In the operation of thesharpener, apenoil is inserted in the chuck andpressed downward into the opening 7. The knives are rotated by means ofthe handle 9 and the knives cut the wood from the pencil, and, at thesame time, gradually draw the pencil downward until it rests upon thestop 29. Between each cut of the knives the toothed wheel 12 is engagedto move the pencil chuck through a partial rotation.

It should be understood that the invention is not limited to the detailsof construction herein shown and described, but may be modified invarious ways without departing from the spirit and scope of theinvention.

I claim as my invention:

1. A chuck for pencil sharpeners having pivoted gripping jaws, andcoiled springs acting on said jaws and tending, to swing them inwardly,said springs extending 1on gitudinally alongside of the jaws.

2. A pencil chuck comprising a sleeve adapted to receive a pencil andhaving openings in its sides, a housing attached to said sleeve,U-shaped .pencil gripping jaws extending through said openings inposition to grip a pencil, each of said jaws being pivoted by the freeend of one of its arms, and coiled springs each bearing at one endagainst said housing and at its other end upon the other arm of one ofsaid U-shaped aws.

3. A pencil chuck comprising a sleeve adapted to receive a pencil, andhaving openings in its sides, a flange fixed to the upper end of saidsleeve, a housing secured to said sleeve, a plurality of pencil-gripgingjaws extending through said open ings in position to grip a pencil, eachof said jaws being of approximate U-shape and having the free end of oneof its arms pivotally supported by said flange, and coiled springs eachbearing at one end against said housing and at its other end;

against the other arm of one of said U- 10 tioned diagonally withrespect to said sleeve,

each of said springs bearing at one end against one of said fingers, andat its other end against said housing.

In testimony whereof I aflix my signature in the presence of twoWitnesses.

CHARLES C. SPENGLER.

Witnesses:

GUST IIAKSTROM, EDMUND H. RUK.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. 0.

